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Date: Wed, 29 Jan 2025 06:54:48 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Dan Carpenter <dan.carpenter@linaro.org>, linux-kernel@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2][next] container_of: add container_first() macro
Message-ID: <2025012955-hypnotic-patronize-8931@gregkh>
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On Wed, Jan 29, 2025 at 03:56:01PM +1030, Gustavo A. R. Silva wrote:
> This is like container_of_const() but it contains an assert to
> ensure that it's using the first member in the structure.

But why?  If you "know" it's the first member, just do a normal cast.
If you don't, then you probably shouldn't be caring about this anyway,
right?

> 
> Co-developed-by: Dan Carpenter <dan.carpenter@linaro.org>
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
> ---
> 
> I will be using this in my -Wflex-array-member-not-at-end patches. :)

Confused, I'd like to see some users first please.

thanks,

greg k-h